Induction Heating-Assisted Compaction in Porous Asphalt Pavements: A Computational Study

Abstract

Low temperature asphalt (LTA) technologies, such as warm-mixed asphalt mixes, are utilized in the paving industry to lower energy demands and greenhouse gas emissions during asphalt mixing and pavement construction. However, the asphalt mixes developed that incorporate LTA additives are more sensitive than hot-mixed asphalts to temperature reduction during compaction, which leads to inadequate compaction and subsequent poor pavement performance. The induction heating-assisted compaction of pavement structures appears to be an effective way to ameliorate such issues and to improve mix compactability at lower temperatures. Considering that induction-assisted compaction is a complex process, a computational methodology is proposed in this paper. A porous asphalt concrete mix was considered as case material. For the pavement compaction analyses after induction, the temperature field generated by electromagnetic induction was predicted and the material parameters of asphalt mortar were adjusted. The effect of induction heating on asphalt compaction effectiveness, the tendency of mix density changing, the increase in compactor passes, and the influence of temperature on compaction at different locations in the pavement were studied as well.

The Influence of Water on the Heat Loss of Hot Mix Asphalt

“…The influence of the water temperature on the amount of the energy required for the vaporization is insignificant. Assuming the constant thickness of water pool the value of natural convection heat transfer coefficient can be determined with equation (6) for laminar flow (∝ l f ree ) and equation 7for turbulent flow (∝ t f ree ) [12]:…”

“…where: T m -the average of the initial HMA surface temperature and the initial water temperature [K]. Equations (6) and 7were derived on the basis of experimental results with the value of A constant determined for a water film with a constant thickness and temperature. Actually, during placement of HMA both the thickness and temperature of the water film vary both for water present in the damp substrate (the bottom surface of HMA layer) and for water used for wetting steel wheels of compacting rollers (the top surface of HMA layer).…”

“…It is determined during compaction. The effectiveness of this process depends on the compaction effort, time and the temperature of the mix being compacted [1][2][3][4][5][6]. The compaction effort and time can be relatively easily controlled by adjusting the number roller passes on the same path during a given time period.…”

Analytical Modeling of the Temperature Using Uniform Moving Heat Source in Planar Induction Heating Process

“…Induction heating usually is applied as the main heating means in various heat treatment processes [1,2], for example, induction hardening, tempering, stress relieving. Besides, induction heating technology also can be used to assistant some other industrial processes, such as crack detection, depth determination [3], induction heating-assisted compaction [4], etc. In these traditional induction heating processes, the shapes of the induction coils are mostly spiral, that is, the parts to be heated are cylindrical parts.…”

Control the crosslinking of epoxy-asphalt via induction heating

“…Within this framework, road authorities, contractors and material suppliers have started to explore new technologies to minimise the energy footprint of pavements and to leverage the economic benefits by developing eco-friendly solutions. One of these technologies is the electro-magnetic induction for heating the asphalt paving materials for improving healing (Garcia et al 2009, Liu et al 2013, Apostolidis et al 2016 and compaction (Bueno et al 2018, Zhou et al 2018. However, asphalt mixes, which are the most commonly used materials in the pavement industry, are non-inductive.…”